High-intensity strength training produced significant improvements in quality of life, mood and motor function for older patients with Parkinson’s disease, according to a new study.

Researchers at the University of Alabama at Birmingham published their findings Jan. 9 online in the Journal of Applied Physiology.

For the study, 15 patients with moderate Parkinson’s disease underwent 16 weeks of high-intensity resistance training combined with interval training designed to simultaneously challenge strength, power, endurance, balance and mobility function. Before and after the intervention, the subjects were compared to age-matched controls who did not have Parkinson’s disease and did not undergo the exercise regimen.

“We saw improvements in strength, muscle size and power, which we expected after rigorous weight training; but we also saw improvement in balance and muscle control,” lead author Marcas Bamman, PhD, professor in the Department of Cell, Developmental and Integrative Biology, said in a news release. “We also saw improvement in cognition, mood and sense of well-being.”

Bamman, who leads the UAB Center for Exercise Medicine, devised a strenuous exercise regimen for the participants. Subjects performed three sets of eight to 12 repetitions of a variety of strength-training exercises, such as leg or overhead presses, with a 1-minute interval between sets for high-repetition, bodyweight exercises, such as lunges or pushups.

“We pushed these patients throughout the exercise period,” Neil Kelly, MA, a graduate student trainee and the study’s first author, said in the release. “We used a heart rate monitor to measure exercise intensity — keeping the heart rate high through the entire 40-minute session.”

Researchers also studied the biology of the muscles using biopsies of muscle tissue that were collected before and after the 16-week study period.

“We found favorable changes in skeletal muscle at the cellular and subcellular levels that are associated with improvements in motor function and physical capacity,” Bamman said in the release.

Study participants showed significant improvement of 5.7 points on average on the Unified Parkinson’s Disease Rating Scale. On another measure, a seven-point fatigue scale, the group also showed a reduction in fatigue severity.

A sit-to-stand test showed that after strength training participants dropped from requiring 90% of maximum muscle recruitment to rise to a standing position to just 60%, which put them on par with their same-age peers without Parkinson’s disease.

“These are all indications that strength training produced a major improvement in the ability to activate muscles, to generate power and to produce energy, all of which can contribute to improved quality of life and reduction of injury risk from falls,” Bamman said in the release.

He said larger studies are needed to define optimal exercise doses for Parkinson’s patients across the disease spectrum.